How Morphology Affects Singlet Fission in Crystalline Tetracene
- 5 May 2015
- journal article
- research article
- Published by American Chemical Society (ACS) in The Journal of Physical Chemistry Letters
- Vol. 6 (10), 1841-1846
- https://doi.org/10.1021/acs.jpclett.5b00569
Abstract
The dependence of exciton dynamics on the crystalline morphology of tetracene is investigated using time-resolved photoluminescence. Single crystals exhibit relatively slow singlet decays with times that range from 130 to 300 ps depending on the sample. This decay has an activation energy of ∼450 cm(-1) over the temperature range of 200-400 K. Single-crystal samples also exhibit more pronounced quantum beats due to the triplet pair spin coherences. Polycrystalline thin films grown by thermal evaporation have singlet decay times on the order of 70-90 ps with a much weaker temperature dependence. Many thin-film samples also exhibit a red-shifted excimer-like emission. When a polycrystalline thin film is thermally annealed to produce larger crystal domains, single-crystal behavior is recovered. We hypothesize that the different dynamics arise from the ability of singlet excitons in the thin films to sample regions with defects or packing motifs that accelerate singlet fission.Funding Information
- Division of Chemistry (CHE-1152677)
This publication has 47 references indexed in Scilit:
- The Dynamics of Singlet Fission in Crystalline Tetracene and Covalent AnalogsAccounts of Chemical Research, 2013
- Singlet FissionChemical Reviews, 2010
- Can up- and down-conversion and multi-exciton generation improve photovoltaics?Solar Energy Materials and Solar Cells, 2008
- Solar conversion efficiency of photovoltaic and photoelectrolysis cells with carrier multiplication absorbersJournal of Applied Physics, 2006
- Temperature dependence of the triplet exciton yield in fission and fusion in tetraceneThe Journal of Chemical Physics, 1981
- Kinematics of triplet pairs in anthracene and tetracene crystalsChemical Physics Letters, 1978
- Exciton fission and annihilation in crystalline tetraceneAustralian Journal of Chemistry, 1977
- Fluorescence decay time measurements in tetracene crystals excited with synchrotron radiationOptics Communications, 1976
- Fission rate of singlet excitons in a tetracene crystal measured with picosecond laser pulsesOptics Communications, 1973
- Fluorescence decay time measurements in tetracene crystalsChemical Physics Letters, 1972